Pocket is an excellent tool that helps you capture information, links, images and content from the web, store it and search through it when needed.
IFTTT
You can sync two apps together, so that when one app completes its tasks, the other starts working on its own tasks.
mentionlytics
Do you want to be up-to-date with your most relevant topics? Mentionlytics searches for given keywords across social media, online news, blogs and other websites.
streak
This tool allows you to track your emails, so you'll know when and whether the recipients have opened them.